1991 TBI using 99 Vortec longblock, Urgent

I have a 91 chevy 2500, 350 TBI ,
fuel injection. I'm going to rebuild a block and put a
edelbrock TBI manaifold on it and use the stock
Throttle body injection on it and all wiring will be
easy. New cam and lifters and use stock heads that
will be tricked out just a little. I hoping to achieve
about 275+ HP with some good bottom end torque. I have the opportunity to get a 99 chevy vortec block and heads. do you know if an Edelbrock #3704 TBI manifold will fit on this long block and if it will bolt up to my tranny. I want to use the stock TBI set up for ease of use. I have found conflicting info about this casting number , whether it is a 2 or 4 bolt main . Casting Number 10243880...350...95-99...4...Gen.I crate motor, "ZZ4", roller cam, one piece rear seal. this info is from http://www.charlottecountyspeedwayinc.com/ajf36/casting_numbers.htm and Mortec shows 2-4 bolt. any help-?
thanks
Ron

I have a 91 chevy 2500, 350 TBI ,
fuel injection. I'm going to rebuild a block and put a
edelbrock TBI manaifold on it and use the stock
Throttle body injection on it and all wiring will be
easy. New cam and lifters and use stock heads that
will be tricked out just a little. I hoping to achieve
about 275+ HP with some good bottom end torque. I have the opportunity to get a 99 chevy vortec block and heads. do you know if an Edelbrock #3704 TBI manifold will fit on this long block and if it will bolt up to my tranny.

I know I'm probally a little late, but here is my 2 cents.

Trash your stock swirl port heads. They are not worth the time or money to trick them out.

Get those 99 Vortec heads. casting number should be 10239906. They will bolt up to your exiting block.

Then buy yourself the GM Vortec TBI intake P/N 12496821.

That intake will bolt up the Vortecs, your stock intake will not.

You can then bolt your TBI unit up to it & do your chip tuning.