Pedal Geometry - 69 Camaro T56 w/DSE MC Bracket -Use OEM Pedals w/Mods or Aftermarket

[DETON8R]

I'm getting ready to set up my clutch master cylinder and it looks like I'm going to use the DSE bracket, as I've already got the GM style Clutch Master Cylinder and throwout bearing set up for mt T56.

I'd like to use the stock brake and clutch pedals, then add aftermarket pedal covers. However I've seen several posts that the stock pedal geometry isn't the greatest, especially when the placement of the accelerator pedal is considered. I've seen a few custom set up's, one in particular is a MOMO pedal that replaces the Lokar gas pedal. Makes it wider and easier to heel-toe.

I've seen posts and the diagram from Street & Performance where there is a metal tab that you weld on the stock/OEM clutch pedal arm if I'm going to modify and use an OEM clutch pedal.

So I guess to restate the question?????

Is there an advantage to forgetting about the OEM pedals and going with all aftermarket pedal assemblies for all three pedals over modified OEM style pedals (pedal covers for brake and clutch) and adjustable gas aftermarket pedals (Lokar, Billet Specialties, EMS)? If you are suggesting aftermarket replacements for OEM what brand, and what is the benefit??

And is there a good reason to weld on the DES bracet to the firewall? Or just fabricate a gasket and RTV the heck out of it? I'm able to box in the bottom part of the bracket with sheet metal if necessary too close up the opening. I know I have to make the firewall opening bigger anyway, I'd just like to know if there are any concerns with leaks or air flow into the cabin.