I always make new panels using 3mm ply ,use the original panel as a template and using plastic inserts like these
eBay item number:
251707545255
I also use B&Q silver insulation on the back of it ,this gives it a sound deadening and thermal quality .
ThermAll Bubble insulation roll, (L)7.5m (W)0.6m (T)4mm
I have used this in my T5.1 camper and 2 T6 vans now and works great,the new panels have stretch carpet on the front and the silver insulation stuck to the back of the panel using the trim spray glue.
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