[Yaesu] Experience needed FT-620B

[Hamel Family]

Here's the basket case again.
Somebody jammed the slugs against the top of the cans in the bandpass filter
between the RF amp and first receive mixer. Sensitivity is way down.
I pulled one can and can see no nondestructive way to free up the slug.
I have used the soldering iron method of loosening the wax mentioned in the
book, but the wax is gone on these cans.
The RF amp is in a socket. Is that normal, or was it a mod?
I found a can of freeze mist, the s-meter reading doubles when the RF amp
3SK40 transistor is cooled.
Did it have a heat sink originally?
Does anyone have a "400" board for the 620B, the replacement slugs, or can I
still buy the cans or slugs from Yaesu ??
Thanks for your time and advice.
Pat Hamel (W5THT)