This is taken directly from the Workshop Manual 1961-1965 Volkswagen 1200
Basic Dimension for Body Repairs:
Width of front apron at first fender securing nut 600mm
Width of tank supports, side to side 693mm (Measured inside tank supports)
Width of tank supports, fore and aft 368mm (Measured inside tank supports)
Distance between first and last fender securing nuts on front side panel 1118mm ( Left hand side of vehicle measured at hole centers.
Distance between first and last fender securing nuts on front side panel 1120mm (Right-hand side of vehicle, measured at hole centers.
Distance from lower welding seam on hinge pillar to upper corner roof member/quarter pannel 1394mm (Left-hand side of vehicle, diagonal measurement of door opening.
Distance from lower welding seam on hinge pillar to upper corner roof member/quarter pannel 1394mm (Right -hand side of vehicle, diagonal measurement of door opening
Distance between hinge pillar and quarter pannel 935mm (Left-hand side of vehicle, door opening at striker plate level.
Distance between hinge pillar and quarter pannel 937mm (Right-hand side of vehicle, door opening at striker plate level.
Distance between hinge pillar and quarter panel 924mm (Left-hand side of vehicle, door opening at side member level.
Distance between hinge pillar and quarter panel 923mm (Righr-hand side of vehicle, door opening at side member level.
Distance between roof and side members and quarter pannel 1049mm (Left-hand side of vehicle)
Distance between roof and side members and quarter pannel 1049mm (Right-hand side of vehicle)
Width of body interior between spot welded flanges of quarter panel window openings level with safety belt anchorages 1023mm
Width of luggage compartment floor between wheel housings along spot welded seam 939mm (measured at holes in luggage compartment floor.
Distance between front corner side members/cross panel and rear corner side member wheel housing 1989mm
Diagonal measurement of interior, left front-right rear, measured on side member
Distance between front corner side members/cross panel and rear corner side member wheel housing 1985mm
Diagonal measurement of interior, right front-left rear, measured on side member
Width of rear apron at lowest fender securing nut 748mm
Distance between cross member and rear hole for bumper bracket screw 1133mm (Left-hand side of vehicle, measured to center of hole.
Distance between cross member and rear hole for bumper bracket screw 1135mm (Right-hand side of vehicle, measured to center of hole
Distance between right and left engine cover plates on front engine cover plate 748mm
Distance between right and left side panels in engine compartment on upper radius of hood opening 909mm
I hope this helps you out, spent about 20minutes typing all this stuff, its in the Bentley Manual . I could not see if there is anything for the convertible so I hope this helps.
Thanks,
Shawn