ok this is how my conversion went:

1.take apart the 4-in-1

2.separate the receiver from the gyro/esc's

3. bend the pins for channel 3 upwards, (be very gentle and do this slowly because they might break)

4.take a dremel tool and shave away the part of the casing above the pins.

5.put back together the casing and plug in the brushless esc.

This worked great for me and didnt involve ANY soldering, sorry i have no pics..no camera

good luck!
-scott

for safety you can disconnect the brushless esc positive (middle wire) from the 4n1. the stock rx is already powered from the bec on the stock esc/gyro/mixer unit. using 2 separate power supplies can create problems.

btw, nice idea, and you are brave to bend the pins. whenever i go brushless, i plan to split the 4n1 in 2 shrinkwrapped peices and connect them together and to the esc with homemade y-adapters. i figure it'll save some weight and i can mount the rx farther from the escs.

what would happen if i didnt disconnect the middle wire?
i've never seen anyone do that in any other conversion before, just asking.

the bec on either side can fry, or there may be glitching. i've read about it in another forum that has a ton of posts on the subject of 4n1 hacking. most of the latest posts agree that cutting the brushless bec wire yeilds the best results.

theoretically, the bec's have identical output voltages and perfect current balance, so connecting them in parallel would be fine. in reality, no 2 regulators will produce identical voltages at all loads, so connecting 2 power supplies in parallel is hazardous. the imperfect outputs may oscillate, creating spikes in voltage and current which can make the rx glitch or fry a bec's voltage regulator.