Help with a 58 300GH Hydra Matic retrofit

[1project2many]

Although not a biggie, and someone correct me if I'm wrong on this, but I don't think any of the Hydramatic trannys ever came with a remote filler tube like newer cars have. Both of the one's that I've had had a short dipstick that was under a plug in the floor beside the hump and you had to lift the mat and remove the plug to check or add fluid to the tranny.

I've never seen a remote check / fill point but I wonder what (if anything) might have been done differently in a step-van chassis.