You better take up Brian's offer.
The stock 914 wheels all have similar offset. I used to run steel 914 wheels with 40mm of offset. Everything fit well under the fender, but the tire being so far in caused it to rub on the front of the lower control arm on tight turns. When I adjusted the stops to stop the rubbing, the turning circle was massive. I think Brian's genuine Porsche wheels have less offset than the steel wheels I used to use, also, the dropped spindle's extra offset helps, but not for you. A small spacer might help.