Michael, just replied to your email.
We have actually spent a lot of time and effort in designing our PACE 427 to maximise interior space.
I believe we can accommodate very large and tall drivers out of the box with our standard PACE 427. We are happy to customise fitment further if required.
Dimensions:
From front of pedals to backrest of seat 1120mm
Width of footwell 400mm
Maximum width of seat 520mm
Photo attached of Don who I believe is 6'5" tall seated in our PACE 427 with a full thickness sprung seat. He could even have sliding seat and sit that low.
And our pedals are lower than the seat base which gives plenty of clearance to dash and steering wheel.
I believe we have created a cockpit that is larger than that found in 4" stretched cars.