Before Heading Out Onto The Asphalt

It's best to ensure that your new acquisition has undergone a proper tune up and inspection for mechanical defects. The following is what I would consider necessary for reliability and safety! 

Minor mechanical checklist to ensure cars roadworthiness

• Drain engine oil, replace  oil filter element and fill engine with approx 5 Quarts 20W-50 
• Change sparkplugs      

  Bosch

  NGK

  Champion

  7597/W7BC

  4611/BP6HS

  312/L87YC

   ***  plugs should be pre gapped to 0.027"

• Change condenser and points. 
• Add a drop of lightweight oil to distributor shaft beneath rotor 
• Check distributor cap for cracking or corrosion of contact stems - replace cap if necessary.  
• Check distributor wires for brittleness -change wires if necessary 
• Check that wires are on correct plugs (firing order is 1,3,4,2,,,#1 is at the front end of the motor ( remember distributor rotates counterclockwise)
• Check fan belt for fraying or brittleness -change if necessary.  Loosen  generator adjustment bolt and apply pressure downward onto generator with a crowbar until there is approx 1/2" of play when pushing against the middle of the belt with finger. Tighten bolt.
• Close fuel valve or clamp fuel intake rubber hose line before fuel pump with vice grip. Detach glass fuel bowl located on underside of fuel pump casting and clean out sediment from bowl and screen
• Replace any inline fuel filters if installed.
• Unscrew carb float bowl lids, drain fuel and empty sediment, check float needle valve operation and check float gap level
• Detach & clean air filters (if metal type soak in varsol or degreaser)
• Check rubber fuel lines for brittleness and leaks especially near clamps (change if necessary)
•  Flush radiator with radiator flush and replace coolant with new antifreeze/water (mixture of  50% antifreeze and 50% water)
• Check all radiator hoses for brittleness and leaks
• Top up brake fluid (use ONLY Girling or Lockheed Dot 3 brake fluid or your brakes will seize)
• Check all brake and clutch lines for corrosion and bleed all 4 brakes and clutch.
• Top up carburetor dampers with lightweight damper oil 
• Check transmission oil fluid level (Use An API GL4 specification gear oil is best, such as "Castrol EP-80" (SAE 80W)
• Time engine:
  1) Set vacuum advance to zero mark on distributor and loosen distributor clamp bolt.) Remove #1 spark plug and turn the engine over by hand so that the No1 piston is coming up to Top Dead Center (T.D.C.) on the compression stroke. (you stick your finger into the #1 spark plug hole and feel the pressure develop in the cylinder)
  2) Continue turning the engine by hand until the timing mark on your bottom
  pulley is aligned with the timing pointer. (the timing mark on the pulley is
  a tiny hole toward the outside edge) You will then be at T.D.C.
  3) Turn the knurled vernier nut on the distributors vacuum advance so that
  it is at the first division (ie. zero)
  4) Rotate your distributor to the highest point on the cam and set your
  point gap to 0.015", tighten the points and tighten the distributor holding bolt
  5) Turn the vernier nut of the vacuum advance and set the indicator to 8 degrees for TR3 motor or 5.5 degrees for TR4  (each division corresponds to 4 degrees) 
  Voila! But remember that even after you time according to the manual, plan on doing some fine tuning of the distributor position on the road. It is an imprecise science:)
• Synchronize carbs, adjust jet mixture and set to proper Idle RPM (600-700 RPM
• Check tire pressure, verify lug nuts are tight on each wheel. In the case of wire wheels ensure that spokes are all tight. Change any spokes that are damaged.
• Check ball joints, tie rods and steering for excessive play
• Check universal joints for excessive play
• Check fluid level in differential top up with GL5 "Castrol EPX 80W-90" (SAE 80W/90)
• Grease all ball joint, king pin and steering joint grease nipples (and water pump if original type)
• Check suspension - replace broken coil or leaf springs and worn shock absorbers
• Verify exhaust system - replace broken manifold studs, corroded exhaust pipes or muffler
• Adjust handbrake
• Verify turn signals, brake and headlamps for proper operation.
• IF YOUR HEAD HAS NOT HAD IT'S EXHAUST SEATS REPLACED WITH HARDENED SEATS REMEMBER TO ADD A LEAD ADDITIVE WITH EACH TANK OF GAS!

The SU Carburetor Type H - tuning, adjusting and servicing instructions
The British Motor Corporation Limited 1965 Http://www.tr-register.com.au/Files/technical.htm

Although the above should not be considered exhaustive, your car should now be roadworthy!