Question on sealing setback pump

[BrendellaJet]

I installed my transom plates this weekend and sealed them to the boat(have not yet sealed them around the pump. I installed throughbolts along the top and sides, however along the bottom beneath the intake, there is nothing I can do to bolt the plates through the transom. Has anybody done anything about this?
My first thought was to drill a hole through the plates, into the intake & then tap the intake, but I dont know how much material there is so I dont want to muck it up...
Another option I have considered is bolting some angle to the bottom of the intake(above the ride plate) using existing holes and jamming the angle against the plates...
Here is an old pic of the area I am working with. Pump is a jacuzzi.
http://www.***boat.com/image_center/data/500/pump_rear-modified.JPG
Thanks for any advice

[bead]

those last two bottom holes are a pain . stuck wood screws w/ lots of silicon in mine . wiped excess off . more silicon around transome adaptor . let it set up and forget about it .

[LGCDEVIL]

those last two bottom holes are a pain . stuck wood screws w/ lots of silicon in mine . wiped excess off . more silicon around transome adaptor . let it set up and forget about it .
ditto

[Nucking futs]

My intake is drilled and tapped,but its an R intake.
BJ, what is the measurment from the pump to the plates you need to seal around your pump? My plates sit about 5/16" off the suction housing, I hope thats not to big of a gap.

[BrendellaJet]

My intake is drilled and tapped,but its an R intake.
BJ, what is the measurment from the pump to the plates you need to seal around your pump? My plates sit about 5/16" off the suction housing, I hope thats not to big of a gap.
Not sure what you are asking, do you meen the gap between the plates and the pump? If so Im looking at 1/8 to 3/16 in some spots.
Your gap sounds a little big, any way you can trim the center on the plates to bring it in a little? If not, just use more silicone!

[tahitijet]

mine is 2 sets of plates a large plates around the full pump with a dish for the hand hold cover then 2 side pieaces that but up to the pump i just made my plates thick enough not to flex, put a bolt in each corner as low and inboard as possible and plenty of silicone on the base plate then around the pieaces. no leaks.
NF 5/16 seems like a large gap from the pump to the sealing surface. thats putting alot of faith in silicone. i cut mine very very close (1/16 to 3/32 at the very max.. ) figuring the tighter it is the better.

[Bitchslapped]

Most custom transom plates have the split in the middle under the pump. Just drill a hole in the middle between the middle and the outside of the plate. Countersink the plate and drill a small screw starter hole. Install one screw on each side. Most transoms are solid fiberglass down there. Finish with silicone. BS

[BrendellaJet]

Most custom transom plates have the split in the middle under the pump. Just drill a hole in the middle between the middle and the outside of the plate. Countersink the plate and drill a small screw starter hole. Install one screw on each side. Most transoms are solid fiberglass down there. Finish with silicone. BS
This is what I have been contemplating. I do have a split in the middle. If I drill a hole as close to center of the two plates & into the glass, I bet I could tap the glass and thread it in there....