73T CIS engine number
 

Well I've located a replacement engine for the 73T and checking the engine number - 6135723, my ID listing is a little off. I'm hoping someone with a more in depth listing might be able to confirm this is a 73T CIS engine.
6 = Engine designation, 6-cylinder unit.
1 = Engine type, 911T-E (1972 or 1973, 911T 2.4 l [2341 cc], 140 hp, MFI).
3 = Model year, 1973.
5=?????

0, 1, 2, 3 or 4 for engine type 911/51 for manual transmission; 9 for engine type 911/61 for Sportomatic transmission.

So the question is, what is the 5 mean?

THANKS IN ADVANCE
Rob

I do not know the engine numbers from the top of my head but the engine type, manual trans, is 911/91. It is also the only engine where the injectors goes into the cylinder head, not the runners.

engine numbers 6133001 to 6136092 are 73 911T US CIS, yours is just number 5723 i reckon. (source redbook)

Thanks for the verification.
You guys are the best!
Rob