Hi there! Building a firetruck is the most fun ever! I'm the one making the yellow Scania in one of frizzen's links earlier. Feel free to send me any questions about anything.
I've been using 0.080 and layered 0.040 Evergreen styrene with Tamiya Extra thin cement normal and quick version. It's a solvent that quickly liquifies the styrene and then quickly evaporates. By holding the pieces together and applying a small drop you can tack them together in a second. If you squeeze the joint and apply a good amount of cement, you'll see the liquid styrene ooze out and get a very solid joint.
I extended the cab into a crew cab and it feels strong enough that I would trust it in a roll over, but the large water tank module definitely will not (yet). The smaller pump module in the middle might. Hopefully I'll never get to test it.
Plans and stuff:
Any measurement you can get on the 1:1 truck will help. I found some photos taken at long range with minimal distortion at reasonably close to 90 degree angles, front, side and back. I then took photos of the model truck from the same angles with a telephoto lens from a distance, with a ruler in the picture. I overlayed those on the photos of the real truck making sure to scale it as close as possible and used the ruler in the picture to get properly scaled measurements
