Any work been done to the heads ? How tall of tire ? With tall tire you need more gear.
No way on the hydraulic roller, stick with a tight lash solid roller around 250 @ 50 600 lift.
You need more convertor I highly recommend the Turbo Action 17805-ST 3,800. The ST stands for street tight and it will work great with your combination on the street I've ran it with your same combination for 6 years now in my 70 pro street Cuda. The convertor is locked up during normal in town crusing and driving but when you put the power to it that's when it will flash the rpm to free up the engine. Do not use a 2,800 you will not like it it's to tight for the engine to work good. I have a 31.5 x 18.5 tire and run a 4.10 gear, 3,000 rpm at around 60-65 mph. Above 3,000 the secondaries come in and it sounds great but it drinks fuel at that point. I get 9.5 to 10 mpg with normal driving.

Logan426