Note: The following blog was written on Dec. 20, 2003

According to generic or Shen's Flying Star, one way to
upgrade P7 houses to P8 is relocating door to a "wang"
position (palace with 8 or 9 water star).

It is correct to a certain extent.

Try this example:

ren mountain, bing facing house with bing door

(ms, ts, ws)

263 727 945
154 372 599
618 836 481

Bing door was a "wang" door during P7. So the logical
choice will be relocate your door to Gen palace with
8ws, is it?

If you do so, you may have over 50% chance of causing
severe damages to your clients, including loss of life
and wealth.

I'll explain this in my "P8 Feng Shui Toolkit"

But in case you can't come for any reason, here is the
hint-- look at the 24 mountains.

Ken Lai