PC Engine GT Cap 504 and 103 function.

[haightc]

What is the function and path of these two capacitors?
When recapping the pad came off on the positive end.  My first attempt using solder paste didn't hold the cap down.   So I have tried again by scraping the top layer of the top of the lead, then I drew the pad and line out to the trace.   I did this last night so i should be able to test how well this worked later this evening.    103 was worse as the positive end pulled up a good share of the trace, also I notice the other pad had came off.   From what I can tell these both have pretty short though path that go to though holes.    My thought is that if the circuit pen method doesn't work I might be about to use a radial cap as a replacement and solder it there.   503 lead to a wide path so my thought is a could use radial there to bridge a path if required. 
Do you think this a reasonable approach?   
Are my assumptions correct?

[thesteve]

103 + goes to a via by the headphones jack and 504 is across the 5V bus
jumper it in or use radial is fine

[haightc]

I replace those spots with radial caps and the replacements seem nice and secure.    However it doesn't turn on, I checked and found 5v in several places.      I did notice two legs were really dark around the transformer (t900)    When I tried to clean around it inductor L900 just fell apart  and crumbled off the pad.   Do you happen to know the spec on this, I want to say it said 101K?

Assuming it is 101kn this would mean it should be rate for 100uH ±10%.   The old inductor had four legs but there are just two large pads underneath.    I order a one from amazon last night hopefully and initial guess on the remainder specs will be correct.

[thesteve]

dont know the spec on L900 (or location for that matter)
T900 is the backlight transformer for the fluorescent lamp in the display

[haightc]

L900 is underneath the foam next to the backlight transformer.
I bought a couple different isolators that just arrived this morning.

I installed this one:
https://www.amazon.com/Uxcell-a13070600ux0394-Radial-Leaded-Inductors/dp/B00EZA7OC8
The system turn on fine and the screen looks great, however the back light is not adjustable.   I can't see any difference then I rotate the knob.   I try one of my other isolators to see if it responds better, I should probably examine the transformer output as well.

[thesteve]

the backlight isnt adjustable on these, so not an issue