how do I find the Production numbers for 91 with the 305 ho and 5 speed

You dont, there are no combination production numbers, probably the best you could accomplish is to take the total number of 305 TPI, total number of M5 trans, and go from there. You might be able to do some math and get a general idea... I have NO Idea what the production numbers were but here is an example.

If there were 50,000 cars made in 19xx
10,000 of all 19xx them had the 305 TPI
10,000 of all 19xx had the M5

You could probaly guess that 2,000 19xx cars had the combo, but thats as close as you get...

John

Ok but how do I get the numbers to start with ?

There was no 305 HO motor in 91... last year for that motor in the F car was 86, and there were very few then.... so I'd say there were zero

In 1991 the LB9 was referred to as the "HO" engine in the Pontiac dealer brochures.

John

If his car is a base model Firebird it has a L03, which is a TBI.

Could be a Formula as well, lots of people call them Firebirds, forgetting, or ignoring the fact that its a Formula....

But your right, if it is a base Firebird then it would only have the LO3.

John

Yes it is a Formula I was not thinking
the codes are
Gu6
lb9
mk6
mm5
ws6
w66