Anyone have plans or images of such a beast? Thoughts? Ideas?
Look at page 7 of http://www.grampianowners.com/G34/g34_manual.pdf
for a timber cradle for a 34' 12,000 boat.
The drawing is a little hard to make out, but the cradle is 8' wide and you can estimate the other dimensions from that. The uprights look like 4x4s. Check Home Depot for 4x6 and 6x6 landscape timbers for the bigger parts, or nail 2x6s/2x8s together. Of course the "pad" height will have to be adjusted for your boat.
Bolt the major parts together. If you can't get carriage bolts long enough, use threaded rod. 1/2" diameter with washers will be big enough.
If you use some ramps and the mainsheet tackle off your boat, it shouldn't be too difficult to drag the cradle onto your trailer.