spark plugs

hi guys,
my vehicle is an lpg 4.6 1999
it's service time have bought all the filters and plugs.
have just had a thought. do you need different plugs if you run on lpg?. the ref on the plugs are ERR 3799 land rover supplied.
do you know if there is a different gap needed.?
regards
rob j

Mines a 3.5 EFi & I'm using NGKs at the normal gap. Some suggest setting the gap smaller.
Don't use multi-contact plugs unless the vehicles original equipment was of that type.
Some pointers at Hints

NGK BPR6ES - they will do nicely.

thanks guys,
service will begin tomorrow.
regards
robj