Well I guess it depends what you want, the car can be converted to a 4 spd Pistol Grip which would be awesome in a convertable , I am sure the 727 route is easier though anyhting else is more work & $$ to install, you can use the 833 OD version if you want but I would recommend 3.91 gears with that
for the engine the std package I use is Speed Pro L2355F pistons with Ported Open chamber heads & 1.81 exhaust valves , balanced bottom end using steel crank & stock rods with new rod bolts , Michigan 77 brgs , windage tray , 6 Qt Hemi pan ,Double roller timing chain , Engle K 56 or K58 Cam & a 2200-2400 stall converter if you go auto [www.englecams.com] , Holley Street dom intake part # 300-14 , & last a Holley Holley 870 cfm Avenger Carb or 6 pack , I have built a number of this package for my customers & all have been happy / impressed with the power & driveability
If you are going to get a steel crank for the engine you may want to look at 440 source , you could also consider a 500" stroker for similar $$$