Does this fit on the 96 Bonneville L36? and if it does, does anyone have flow numbers for it?

Yes it will fit but you will be missing one vaccum port which is for the shift modulator on the transmisson. Some else will hopefuly chime in wih flow numbers.

can it be modified to accept a the extra vac. port?

Tee off another vacuum line.

Oh okay, thats easy to do. Or can the TB be drilled and taped for an other vac line

It'* actually plugged if I recall properly.

Pulged with a threaded plug? or is it pluged with a press in plug?

I played with a L67 TB(I think it was) that lacked that extra vacuum port. I just used a screwdriver and hammer to knock the plug out. I had a spare throttle body that I had ruined, so I ground the vac port out of it and drove it into the hole that was plugged(after knocking the plug out of course). No threads, just held by friction.

It'* not hard to drill out and put something in there.
I had to when I put a 99+ TB on my 95.
I just found something in my garage with the same diameter, ground it down a little, and epoxied it in.

So anyone got flow numbers?
I know the stock one flowed 440ish cfm at 28" without the screen, but my flow bench is out of commission right now.