yesterday i was preparing the cutting list for the chassis in order to know how much to buy, but after doublec-hecking the measurements, the +4chassis plans do not include the measurements for the transmission tunnel. is this because they are the same as the book chassis? anyway, i couldnt find measurements for the tunnel. the book has to have them right?

When i did mine i just used the length from the rear bulkhead to the first horizontal tube then x4 + 4meters or so so i would have a bit of extra tube in stock if i needed it for other things.

Always buy at least 4-6 metres more than you think you'll need. Chances are you'll cut a tube or two a little short, mess something up, decide to add a tube here and there etc etc. I started off building a +4, but then decided to add loads of extra triangulation. This added at least another 8-10 metres overall.

ok, thanks.
i just dont wanna mess up the height of the transmission tunnel, or the triangulation.

yeah use the book for the trans tunnel dimensions, although you might want to adapt it for what ever engine your using.

Simple tip, don't let your tranny tunnel uprights coincide with the wide bit at the back end of your type 9 (if you are using one)

Don't ask me how I know this