What would be the maximum wheel size front and rear on a Manx body shell thanks in advance Matt

Difficult one that a wheel offset comes into it and on the rear you have shorter drive shafts pre 68 they give you an extra 1.5" a side for a wheel.
Should be around 6" front and 7 or8 for the rear but people have tyres past the body line and run 10" rears. Spotted a pair of 14 x 15 Wheels for sale the other day on e bay Non vw pattern.