[rickst29]

I think that the large number of deck screws is more than sufficient for the entire anticipated load, although I don't intend to actually test that.

All of my deck screws are going through TWO layers of 1-inch wood (not only one). The floor definitely contains more wood along the street side and curb side edges - that's 1 inch thick and possibly more than 1" one wide (horizontal).

Placement of the 4 OEM bolts, holding TM's shorter and thinner L" plates against the floor, seems to imply more than 1" of width in those floor edge boards. But those plates and torsion bar guide holes are probably not carrying significant weight, even in lifted/open configuration.
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All of my pilot holes were cutting into wood (not foam) all the way up. Just two screws easily hold the lower assembly in place, that's maybe 15 lbs all by itself.

I'm unsure of the actual force from these gas struts, the "ratings" may be referring to the weight being lifted. And the gas strut force will be offset from screws, creating torque with a moment arm of about 6" from the row of deck screws. But I think that they could handle all the force themselves; slightly bigger wood screws (#10 or #12) would have provided even more strength than the #9 deck screws.

I'm not going to test that. I will be using the additional 1/4" support bolt holes.