Carlos... & everyone else too
Fiddling under the dash is physical torture!
Especially for old bones that no longer bend and twist with ease, and that are wrapped in muscles that very quickly ache from strain.
But it has to be done!...The 'madness' requires it.
I envision a 'clamped' driver's seat that can easily be removed.
A splined steering wheel (per Wolfgang's suggestion) that simply pulls off the column. The open floor is now padded with a one piece deck lounge cushion that is double folded over the clutch and brake pedals as a head rest. Illumination from two small battery LED's...with perhaps a small cylindrical LED flashlight that can be held in the mouth. A pouch with every miniature tool possibly required resting on your chest.
Oh... and some soft soothing music in the background that sort of drowns out the groaning and cursing.