How can I install a Pitless Adapter in a large diameter corrugated steel pipe?

Installing pitless in corrugated casing
#1 - Assemble 2" pitless (P-200-SS), 2" close sch. 80 pipe nipple, 2" Steel coupling put connections together tightly to ensure
the pitless / nipple will not be able to rotate in the coupling.
#2 - Drill a hole equal to the outside diameter of the 2" coupling in the required location in the corrugated casing (2.75" hole
#3 - Test to make sure the coupling freely pass thru the hole from the outside be fore attempting to install.
#4 - Insert a safety pin inside the pitless to ensure the elbow and slide do not separate during the installation of the pitless .
#5 - Thread the lift out pipe into the 1-1/2" blind hole in the top side of the pitless elbow (long enough to reach the hole for the
pitless with enough pipe extending from the top of the casing + 3-4 feet)
#6 - lower the pitless assembly (pitless, nipple and coupling down the casing and insert he coupling through the predrilled hole.
#7 - Thread the 2" stabilizer pipe into the coupling (3-5 ft. min) to allow for soil compaction which will support and hold the
pitless securely to reduce the stress on the weld connection due to the weight of the pipe column and submersible pump.
#8 - Align and secure both the lift out pipe and the service (discharge pipe) to ensure the pitless adapter is in proper vertical
and horizontal alignment
#9 - Have a certified welder, weld the coupling to the corrugated casing around the entire circumference to ensure that a water
tight connection is made which will prevent any surface water from entering the well to avoid any chance of contamination
(proper breathing filters should be used to weld on galvanized casing - this is not ideal)
#10 - It is recommended to test the system for a significant duration to ensure there are no leaks at any connections prior to
back filling (if this is done make sure the discharge pipe is secured in position.
#11 - Back fill using proper back filling / soil compaction procedures this will support the pitless from being tilted and stressing
the well connection due to the weight of the pump.