It will be cheaper and easier in the long run to put an automatic in there. Either a 727 or something else if you want more gears. Any manual transmission that is going to survive in a heavy car with a bunch of power is going to cost a bunch of money and take a bunch of time. You can build a heavy duty 727 with billet parts and a good converter for $4000 and it will bolt in. If you pick the right converter you'll also be able to drive it on the street as well as make nice solid passes at the track. You'll spend twice that much money for a complete manual, shifter, clutch, bellhousing setup and you'll need to have a chassis shop build a new tunnel in the car for everything to fit.
I just went thru this whole exercise with a customer who dropped a 700 hp 505 inch big block into his B body with a 23 spline transmission. Now he is having a 727 built with billet drum, manual valve body, pro street type torque converter, etc.
Well that might be easier and cheaper but,,,,,,if its not what you want than what's the point?
Easiest approach is sell the car and get a better recliner.
This is a hobby/ sport.
Not saving the world.
Bracket racing is not the only way to enjoy the dragstrip..
If you aren't getting anything out of the challenge and the satisfaction of meeting a goal......well you should not be doing it.
Stickshift stuff isn't for everyone takes a little more time and money and work.
Nobody has ever watched a car tear down the street or strip and say "cool an automatic ".....😏
