E E don't ruin a good boat by making the top Trailer Sailer on the market into a keeler.
Sure, change the foils, but don't remove the lifting keel.
I know it's a grind to pump it up, but once it's gone you'll lose at least $10-15,000 on resale value.
Some of the best sailing (on a mono) was on my Elliott 7.4
Why not try and swap it for an E7.9 then and get a bit more length, then change your foils.