before starting bear in mind these require more work than considered possible. also the processes involved use chemicals that emit various odours and sanding creates loads of dust so a well ventilated or outdoor area is required. lounges/kitchens are not good build creation venues if family relationships are to be retained.
decide on a design (be aware of glovebox opening issues, crossover locations, cable entry into the door plans and feet/leg clearance requirements) and template it out in card then transfer it to mdf:

if door pocket retention is important maybe create a baffle joined to the original pocket (be aware of limited enclosure space issues) otherwise trimming of the metal door handle hook is probably in order:

glue and screw the mdf together and mesh in the corners:

now mix up some fibreglass and filler and apply. for best results especially in terms of strength build up shapes required in layers rather than dabbing it all in at once:

now for the most laborious part - sanding. start with course paper and work up to some finer stuff. several filler - sanding - filler - sanding routines are required to arrive at a good standard of finish:

as the required shapes come into being start using light coats of primer as 'guide coats' - only when some paint is applied do the areas that still need attention become apparent:

finsh as required. if trimming is to happen then only a smooth finsh is required. if a painted finish is required every surface needs to be pretty near perfect:

finally a word about sosts: a motor factors will supply large primer cans for under Ԛ£4, halfords offer a small can for more money. large tubs of filler and fibreglass are the same costs as poxily small tins in halfords from a local grp mouldings firm. mdf is cheaper from a builders merchants than from b&q.
paul




