[1.20.4] to make a minecar rail that works on slabs , maybe also steepladders

im doing a kin of custome mineshaft tunel but whit slabs 
notice minecarts dont works out of minecar rails soo i need to find a way to lay rails on slabs having in account inclination 

Here in the video the minecart stucks on the slab

it can not run over anything different from rail blocks 

i was thinking into extending RailBlock but latter how i make minecrats to aknoledge mi custome rail slab or vainilla rails to connect whit the costume one 

or it is anothe option besides making a custome mine cart and override the vainilla one ??