got chatting to a WC the other day that has done excactly what you want to do, he had 2 unger poles both converted to wfp, wish i had his phone number for you, he did tell me he had got all his stuff from B+Q.
He even used their clear piping all thru his system, not a hose pipe or micrabore in sight!
He only did domestic so had built his system to suit his own needs, was a great little set up.
Good luck.