it will be easy as long as you get the correct sb5101 version and not the u version or the n version
they require spi but thats not hard tho but if your wanting one with a pin header the when you go on ebay and look at the modem make sure it has no other letters after 5101
all you need is solder flux and the iron its super simple dip the bottom of the pin header in the flux put it in the board then put solder on iron and touch
each pin the flux will help to secure the connection and is highly recommended and to do this it would be one of the simplest things to do for a beginer
they require spi but thats not hard tho but if your wanting one with a pin header the when you go on ebay and look at the modem make sure it has no other letters after 5101
all you need is solder flux and the iron its super simple dip the bottom of the pin header in the flux put it in the board then put solder on iron and touch
each pin the flux will help to secure the connection and is highly recommended and to do this it would be one of the simplest things to do for a beginer