To use a rear transverse is a choice you will have to make, here are a few things to consider;
A transverse spring has a center pivot point and tends to roll, this gets worse when a front transverse spring is used also (think of balancing the frame on two jackstands instead of four).
Coil overs tend to have less roll because they are mounted towards the outside of the frame (put two jackstands under the rear of the frame where the coil-overs would mount and one under the front in the center). a bit more stable! Put four under it and you get the idea.
When using a rear spring it will help to use quality rear gas charged shocks as far outboard as possible and would even be better to run an anti-roll bar.
Coil-overs are adjustable in spring rates, spring compression and lengths (some even have shock dampening adjustments). Spring are designed for a specific rate and may have the choice of reversed eyes or standard eyes for height adjustment.
The reason I say it's your choice is that to get the look you may be after, a coil-over set up may not be period correct, but would be the better driving/handling option then the transverse spring/gas shock combo.
Been caught in the rain in ragtops many times, as long as you keep moving, not bad, it's when you slow down you get wet.... I drive like a mad man to find a overpass or similar spot to put the top up. Better not be in the way! Lol.Been caught in the rain a few times, I found out a poncho works the best for rain protection. Has a hood & a lot of materal to cover you up.
Been caught in the rain in ragtops many times, as long as you keep moving, not bad, it's when you slow down you get wet.... I drive like a mad man to find a overpass or similar spot to put the top up. Better not be in the way! Lol.