I've bought, sold, and serviced way more than 100 ST70 amps over the past 10 years, and wish I had a pile of photos showing how poorly some people ship their $500 amplifiers!!
If you throw an amp in a box of peanuts, there's a 99% chance it WILL be DAMAGED. If you pack it properly, their is a 99% chance it will NOT be damaged. Here are the instructions I've had posted on my web site for the past 10 years . . .
All equipment sent to us for service must be shipped as follows:
(2) All equipment must be DOUBLE-BOXED with at least 1 inch
of cushion or foam between the inside box and the outside box, for each 25# of weight.
(if your amp weighs 35#, that's 1.5" all around each side, top, and bottom.
(3) Tubes must be removed from amplifiers and packed with the equipment wrapped in foam or bubble pack
(4) Please use "Fragile" or "Handle with Care" stickers on the box.
(5) You are responsible for providing insurance of the shipment for maximum value of your equipment.
(6) Use FedEx Ground (usually 25% less than UPS) or UPS Ground for shipment of anything weighing over 15#. It is OK to use the Post Office on lighter items (under 15#).